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April 29th, 2019

4/29/2019

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Smart Vents

3/30/2014

2 Comments

 
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Roof and Attic ventilation ports are an important component that often gets overlooked. Often times I see the underside of roof sheathing is black from lack of proper attic-roof ventilation.  Many older homes originally had a wood roof which had lots of openings for ventilation but when a new composition shingle roof gets put on ventilation ports are often ignored.  Some older style homes have no roof overhang or eaves which make traditional soffit vents difficult.  I was very happy to discover Smart Vents from DCI Products on a recent inspection.  They have a variety of ventilation products that look nice.

So don't neglect roof-attic ventilation, especially in cathederal ceilings or you might see this!
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Carbon Monoxide Poisoning

3/1/2014

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Carbon monoxide (CO) is a colorless, odorless, poisonous gas that forms from incomplete combustion of fuels, such as natural or liquefied petroleum gas, oil, wood or coal.

Facts and Figures
  • 480 U.S. residents died between 2001 and 2003 from non-fire-related carbon-monoxide poisoning.
  • Most CO exposures occur during the winter months, especially in December (including 56 deaths, and 2,157 non-fatal exposures), and in January (including 69 deaths and 2,511 non-fatal exposures). The peak time of day for CO exposure is between 6 and 10 p.m.
  • Many experts believe that CO poisoning statistics understate the problem. Because the symptoms of CO poisoning mimic a range of common health ailments, it is likely that a large number of mild to mid-level exposures are never identified, diagnosed, or accounted for in any way in carbon monoxide statistics.
  • Out of all reported non-fire carbon-monoxide incidents, 89% or almost nine out of 10 of them take place in a home.
Physiology of Carbon Monoxide Poisoning
When CO is inhaled, it displaces the oxygen that would ordinarily bind with hemoglobin, a process the effectively suffocates the body. CO can poison slowly over a period of several hours, even in low concentrations. Sensitive organs, such as the brain, heart and lungs, suffer the most from a lack of oxygen.
High concentrations of carbon monoxide can kill in less than five minutes. At low concentrations, it will require a longer period of time to affect the body. Exceeding the EPA concentration of 9 parts per million (ppm) for more than eight hours may have adverse health affects. The limit of CO exposure for healthy workers, as prescribed by the U.S. Occupational Health and Safety Administration, is 50 ppm. 
Potential Sources of Carbon Monoxide
Any fuel-burning appliances which are malfunctioning or improperly installed can be a source of CO, such as:
  • furnaces;
  • stoves and ovens;
  • water heaters;
  • dryers; 
  • room and space heaters; 
  • fireplaces and wood stoves;
  • charcoal grills;
  • automobiles;
  • clogged chimneys or flues;
  • space heaters;
  • power tools that run on fuel;
  • gas and charcoal grills;
  • certain types of swimming pool heaters; and 
  • boat engines. 
CO Detector Placement
CO detectors can monitor exposure levels, but do not place them:
  • directly above or beside fuel-burning appliances, as appliances may emit a small amount of carbon monoxide upon start-up;
  • within 15 feet of heating and cooking appliances, or in or near very humid areas, such as bathrooms;
  • within 5 feet of kitchen stoves and ovens, or near areas locations where household chemicals and bleach are stored (store such chemicals away from bathrooms and kitchens, whenever possible);
  • in garages, kitchens, furnace rooms, or in any extremely dusty, dirty, humid, or greasy areas;
  • in direct sunlight, or in areas subjected to temperature extremes. These include unconditioned crawlspaces, unfinished attics, un-insulated or poorly insulated ceilings, and porches;
  • in turbulent air near ceiling fans, heat vents, air conditioners, fresh-air returns, or open windows. Blowing air may prevent carbon monoxide from reaching the CO sensors.
Do place CO detectors:
  • within 10 feet of each bedroom door and near all sleeping areas, where it can wake sleepers. The Consumer Product Safety Commission (CPSC) and Underwriters Laboratories (UL) recommend that every home have at least one carbon monoxide detector for each floor of the home, and within hearing range of each sleeping area;
  • on every floor of your home, including the basement (source:  International Association of Fire Chiefs/IAFC);
  • near or over any attached garage. Carbon monoxide detectors are affected by excessive humidity and by close proximity to gas stoves (source:  City of New York);
  • near, but not directly above, combustion appliances, such as furnaces, water heaters, and fireplaces, and in the garage (source:  UL); and
  • on the ceiling in the same room as permanently installed fuel-burning appliances, and centrally located on every habitable level, and in every HVAC zone of the building (source:  National Fire Protection Association 720). This rule applies to commercial buildings.
In North America, some national, state and local municipalities require installation of CO detectors in new and existing homes, as well as commercial businesses, among them:  Illinois, Massachusetts, Minnesota, New Jersey, Vermont and New York City, and the Canadian province of Ontario. Installers are encouraged to check with their local municipality to determine what specific requirements have been enacted in their jurisdiction.

How can I prevent CO poisoning?
  • Purchase and install carbon monoxide detectors with labels showing that they meet the requirements of the new UL standard 2034 or Comprehensive Safety Analysis 6.19 safety standards.
  • Make sure appliances are installed and operated according to the manufacturer's instructions and local building codes. Have the heating system professionally inspected by an InterNACHI inspector and serviced annually to ensure proper operation. The inspector should also check chimneys and flues for blockages, corrosion, partial and complete disconnections, and loose connections.
  • Never service fuel-burning appliances without the proper knowledge, skill and tools. Always refer to the owner's manual when performing minor adjustments and when servicing fuel-burning equipment.
  • Never operate a portable generator or any other gasoline engine-powered tool either in or near an enclosed space, such as a garage, house or other building. Even with open doors and windows, these spaces can trap CO and allow it to quickly build to lethal levels.
  • Never use portable fuel-burning camping equipment inside a home, garage, vehicle or tent unless it is specifically designed for use in an enclosed space and provides instructions for safe use in an enclosed area.
  • Never burn charcoal inside a home, garage, vehicle or tent.
  • Never leave a car running in an attached garage, even with the garage door open.
  • Never use gas appliances, such as ranges, ovens or clothes dryers to heat your home.
  • Never operate un-vented fuel-burning appliances in any room where people are sleeping.
  • During home renovations, ensure that appliance vents and chimneys are not blocked by tarps or debris. Make sure appliances are in proper working order when renovations are complete.
  • Do not place generators in the garage or close to the home. People lose power in their homes and get so excited about using their gas-powered generator that they don't pay attention to where it is placed. The owner's manual should explain how far the generator should be from the home.
  • Clean the chimney. Open the hatch at the bottom of the chimney to remove the ashes.  Hire a chimney sweep annually.
  • Check vents. Regularly inspect your home's external vents to ensure they are not obscured by debris, dirt or snow.
 
In summary, carbon monoxide is a dangerous poison that can be created by various household appliances. CO detectors must be placed strategically throughout the home or business in order to alert occupants of high levels of the gas.

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Ground Fault Circuit Interrupters, GFCI

11/26/2013

2 Comments

 
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A ground-fault circuit interrupter, or GFCI, is a device used in electrical wiring to disconnect a circuit when unbalanced current is detected between an energized conductor and a neutral return conductor.  Such an imbalance is sometimes caused by current "leaking" through a person who is simultaneously in contact with a ground and an energized part of the circuit, which could result in lethal shock.  GFCIs are designed to provide protection in such a situation, unlike standard circuit breakers, which guard against overloads, short circuits and ground faults. 
 
It is estimated that about 300 deaths by electrocution occur every year, so the use of GFCIs has been adopted in new construction, and recommended as an upgrade in older construction, in order to mitigate the possibility of injury or fatality from electric shock.
 
History

The first high-sensitivity system for detecting current leaking to ground was developed by Henri Rubin in 1955 for use in South African mines.  This cold-cathode system had a tripping sensitivity of 250 mA (milliamperes), and was soon followed by an upgraded design that allowed for adjustable trip-sensitivity from 12.5 to 17.5 mA.  The extremely rapid tripping after earth leakage-detection caused the circuit to de-energize before electric shock could drive a person's heart into ventricular fibrillation, which is usually the specific cause of death attributed to electric shock.

Charles Dalziel first developed a transistorized version of the ground-fault circuit interrupter in 1961.  Through the 1970s, most GFCIs were of the circuit-breaker type.  This version of the GFCI was prone to frequent false trips due to poor alternating-current characteristics of 120-volt insulations.  Especially in circuits with long cable runs, current leaking along the conductors’ insulation could be high enough that breakers tended to trip at the slightest imbalance. 
 
Since the early 1980s, ground-fault circuit interrupters have been built into outlet receptacles, and advances in design in both receptacle and breaker types have improved reliability while reducing instances of "false trips," known as nuisance-tripping.
 
NEC Requirements for GFCIs

The National Electrical Code (NEC) has included recommendations and requirements for GFCIs in some form since 1968, when it first allowed for GFCIs as a method of protection for underwater swimming pool lights.  Throughout the 1970s, GFCI installation requirements were gradually added for 120-volt receptacles in areas prone to possible water contact, including bathrooms, garages, and any receptacles located outdoors.

The 1980s saw additional requirements implemented.  During this period, kitchens and basements were added as areas that were required to have GFCIs, as well as boat houses, commercial garages, and indoor pools and spas.  New requirements during the '90s included crawlspaces, wet bars and rooftops.  Elevator machine rooms, car tops and pits were also included at this time.  In 1996, GFCIs were mandated for all temporary wiring for construction, remodeling, maintenance, repair, demolition and similar activities and, in 1999, the NEC extended GFCI requirements to carnivals, circuses and fairs.

The 2008 NEC contains additional updates relevant to GFCI use, as well as some exceptions for certain areas.  The 2008 language is presented here for reference.

2008 NEC on GFCIs

100.1 Definition

100.1  Definitions. Ground-Fault Circuit Interrupter. A device intended for the protection of personnel that functions to de-energize a circuit or portion thereof within an established period of time when a current to ground exceeds the values established for a Class A device.

FPN: Class A ground-fault circuit interrupters trip when the current to ground has a value in the range of 4 mA to 6 mA.  For further information, see UL 943, standard for Ground-Fault Circuit Interrupters.

210.8(A)&(B)  Protection for Personnel

210.8 Ground-Fault Circuit Interrupter Protection for Personnel.

(A)  Dwelling Units. All 125-volt, single-phase, 15- and 20-ampere receptacles installed in the locations specified in (1) through (8) shall have ground-fault circuit-interrupter protection for personnel.

(1)   bathrooms;

(2)   garages, and also accessory buildings that have a floor located at or below grade level not intended as habitable rooms and limited to storage areas, work areas, and areas of similar use;
Exception No. 1: Receptacles not readily accessible.

Exception No. 2: A single receptacle or a duplex receptacle for two appliances that, in normal use, is not easily moved from one place to another and that is cord-and-plug connected in accordance with 400.7(A)(6), (A)(7), or (A)(8).

Receptacles installed under the exceptions to 210.8(A)(2) shall not be considered as meeting the requirements of 210.52(G)

(3)   outdoors;

Exception: Receptacles that are not readily accessible and are supplied by a dedicated branch circuit for electric snow melting or deicing equipment shall be permitted to be installed in accordance with the applicable provisions of Article 426.

(4)   crawlspaces at or below grade level.

Exception No. 1: Receptacles that are not readily accessible.

Exception No. 2:  A single receptacle or a duplex receptacle for two appliances that, in normal use, is not easily moved from one place to another and that is cord-and-plug connected in accordance with 400.7(A)(6), (A)(7), or (A)(8).

Exception No. 3: A receptacle supplying only a permanently installed fire alarm or burglar alarm system shall not be required to have ground-fault circuit interrupter protection.

Receptacles installed under the exceptions to 210.8(A)(2) shall not be considered as meeting the requirements of 210.52(G)

(6)   kitchens, where the receptacles are installed to serve the countertop surfaces;

(7)   wet bar sinks, where the receptacles are installed to serve the countertop surfaces and are located within 6 feet (1.8 m) of the outside edge of the wet bar sink;

(8)   boathouses;

(B) Other Than Dwelling Units. All 125-volt, single-phase, 15- and 20-ampere receptacles Installed in the locations specified in (1), (2), and (3) shall have ground-fault circuit interrupter protection for personnel:

(1)   bathrooms;

(2)   rooftops;

Exception: Receptacles that are not readily accessible and are supplied by a dedicated branch circuit for electric snow-melting or de-icing equipment shall be permitted to be installed in accordance with the applicable provisions of Article 426.

(3)   kitchens.
 
Testing Receptacle-Type GFCIs

Receptacle-type GFCIs are currently designed to allow for safe and easy testing that can be performed without any professional or technical knowledge of electricity.  GFCIs should be tested right after installation to make sure they are working properly and protecting the circuit.  They should also be tested once a month to make sure they are working properly and are providing protection from fatal shock. 
 
To test the receptacle GFCI, first plug a nightlight or lamp into the outlet. The light should be on.  Then press the "TEST" button on the GFCI. The "RESET" button should pop out, and the light should turn off.
 
If the "RESET" button pops out but the light does not turn off, the GFCI has been improperly wired. Contact an electrician to correct the wiring errors.
 
If the "RESET" button does not pop out, the GFCI is defective and should be replaced.

If the GFCI is functioning properly and the lamp turns off, press the "RESET" button to restore power to the outlet.
 
 By Nick Gromicko and Ethan Ward
2 Comments

Anti Scald Valve

11/13/2013

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Anti-scald valves, also known as tempering valves and mixing valves, mix cold water in with outgoing hot water so that the hot water that leaves a fixture is not hot enough to scald a person.
Facts and Figures
  • Scalds account for 20% of all burns.
  • More than 2,000 American children are scalded each year, mostly in the bathroom and kitchen.
  • Scalding and other types of burns require costly and expensive hospital stays, often involving skin grafts and plastic surgery.
  • Scalding may lead to additional injuries, such as falls and heart attacks, especially among the elderly.
  • Water that is 160º F can cause scalding in 0.5 seconds.
Unwanted temperature fluctuations are an annoyance and a safety hazard. When a toilet is flushed, for instance, cold water flows into the toilet’s tank and lowers the pressure in the cold-water pipes. If someone is taking a shower, they will suddenly feel the water become hotter as less cold water is available to the shower valve. By the same principle, the shower water will become colder when someone in the house uses the hot-water faucet. This condition is exacerbated by plumbing that’s clogged, narrow, or installed in showers equipped with low-flow or multiple showerheads. A sudden burst of hot water can cause serious burns, particularly in young children, who have thinner skin than adults. Also, a startling thermal shock – hot or cold – may cause a person to fall in the shower as he or she scrambles on the slippery surface to adjust the water temperature. The elderly and physically challenged are at particular risk.

Anti-scald valves mitigate this danger by maintaining water temperature at a safe level, even as pressures fluctuate in water supply lines. They look similar to ordinary shower and tub valves and are equipped with a special diaphragm or piston mechanism that immediately balances the pressure of the hot- and cold-water inputs, limiting one or the other to keep the temperature within a range of several degrees. As a side effect, the use of an anti-scald valve increases the amount of available hot water, as it is drawn more slowly from the water heater. Inspectors and homeowners may want to check with the authority having jurisdiction (AHJ) to see if these safety measures are required in new construction in their area.

Installation of anti-scald valves is typically simple and inexpensive. Most models are installed in the hot-water line and require a cold-water feed. They also require a swing check valve on the cold-water feed line to prevent hot water from entering the cold-water system. They may be installed at the water heater to safeguard the plumbing for the whole building, or only at specific fixtures.

The actual temperature of the water that comes out of the fixture may be somewhat different than the target temperature set on the anti-scald valve. Such irregularities may be due to long, uninsulated plumbing lines or defects in the valve itself. Users may fine-tune the valve with a rotating mechanism that will allow the water to become hotter or colder, depending on which way it’s turned. Homeowners may contact an InterNACHI inspector or a qualified plumber if they have further questions or concerns.

In summary, anti-scald valves are used to reduce water temperature fluctuations that may otherwise inconvenience or harm unsuspecting building occupants.



by Nick Gromicko
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Solid State Hard Drive

11/3/2013

5 Comments

 
I have recently installed Solid State Hard Drives (SSD) in a couple of our computers and am very happy!  My office computer is over five years old and was running pretty slow, especially when two people were using it.  I kept thinking about replacing it.  With the new SSD, it is amazingly fast, it opens multiple programs very fast, I am very happy!  I got a fast Samsung 840 pro, 256 Gig SSD for $212 delivered, I definatly recommend the upgrade!

5 Comments

Dryer Vent Safety

10/29/2013

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By Nick Gromicko and Kenton Shepard
 
Clothes dryers evaporate the water from wet clothing by blowing hot air past them while they tumble inside a spinning drum. Heat is provided by an electrical heating element or gas burner. Some heavy garment loads can contain more than a gallon of water which, during the drying process, will become airborne water vapor and leave the dryer and home through an exhaust duct (more commonly known as a dryer vent).
 
A vent that exhausts moist air to the home's exterior has a number of requirements:
  1. It should be connected. The connection is usually behind the dryer but may be beneath it. Look carefully to make sure it’s actually connected.
  2. It should not be restricted. Dryer vents are often made from flexible plastic or metal duct, which may be easily kinked or crushed where they exit the dryer and enter the wall or floor. This is often a problem since dryers tend to be tucked away into small areas with little room to work. Vent hardware is available which is designed to turn 90° in a limited space without restricting the flow of exhaust air. Restrictions should be noted in the inspector's report. Airflow restrictions are a potential fire hazard.
  3. One of the reasons that restrictions are a potential fire hazard is that, along with water vapor evaporated out of wet clothes, the exhaust stream carries lint – highly flammable particles of clothing made of cotton and polyester. Lint can accumulate in an exhaust duct, reducing the dryer’s ability to expel heated water vapor, which then accumulates as heat energy within the machine. As the dryer overheats, mechanical failures can trigger sparks, which can cause lint trapped in the dryer vent to burst into flames. This condition can cause the whole house to burst into flames. Fires generally originate within the dryer but spread by escaping through the ventilation duct, incinerating trapped lint, and following its path into the building wall.

InterNACHI believes that house fires caused by dryers are far more common than are generally believed, a fact that can be appreciated upon reviewing statistics from the National Fire Protection Agency. Fires caused by dryers in 2005 were responsible for approximately 13,775 house fires, 418 injuries, 15 deaths, and $196 million in property damage. Most of these incidents occur in residences and are the result of improper lint cleanup and maintenance. Fortunately, these fires are very easy to prevent.

The recommendations outlined below reflect International Residential Code (IRC) SECTION M1502 CLOTHES DRYER EXHAUST guidelines:
M1502.5 Duct construction.
Exhaust ducts shall be constructed of minimum 0.016-inch-thick (0.4 mm) rigid metal ducts, having smooth interior surfaces, with joints running in the direction of air flow. Exhaust ducts shall not be connected with sheet-metal screws or fastening means which extend into the duct.


This means that the flexible, ribbed vents used in the past should no longer be used. They should be noted as a potential fire hazard if observed during an inspection.

M1502.6 Duct length.
The maximum length of a clothes dryer exhaust duct shall not exceed 25 feet (7,620 mm) from the dryer location to the wall or roof termination. The maximum length of the duct shall be reduced 2.5 feet (762 mm) for each 45-degree (0.8 rad) bend, and 5 feet (1,524 mm) for each 90-degree (1.6 rad) bend. The maximum length of the exhaust duct does not include the transition duct.
This means that vents should also be as straight as possible and cannot be longer than 25 feet. Any 90-degree turns in the vent reduce this 25-foot number by 5 feet, since these turns restrict airflow.

A couple of exceptions exist:
  1. The IRC will defer to the manufacturer’s instruction, so if the manufacturer’s recommendation permits a longer exhaust vent, that’s acceptable. An inspector probably won’t have the manufacturer’s recommendations, and even if they do, confirming compliance with them exceeds the scope of a General Home Inspection.
  2. The IRC will allow large radius bends to be installed to reduce restrictions at turns, but confirming compliance requires performing engineering calculation in accordance with the ASHRAE Fundamentals Handbook, which definitely lies beyond the scope of a General Home Inspection.

M1502.2 Duct termination.
Exhaust ducts shall terminate on the outside of the building or shall be in accordance with the dryer manufacturer’s installation instructions. Exhaust ducts shall terminate not less than 3 feet (914 mm) in any direction from openings into buildings. Exhaust duct terminations shall be equipped with a backdraft damper. Screens shall not be installed at the duct termination.
Inspectors will see many dryer vents terminate in crawlspaces or attics where they deposit moisture, which can encourage the growth of mold, wood decay, or other material problems. Sometimes they will terminate just beneath attic ventilators. This is a defective installation. They must terminate at the exterior and away from a door or window. Also, screens may be present at the duct termination and can accumulate lint and should be noted as improper. 
M1502.3 Duct size.
The diameter of the exhaust duct shall be as required by the clothes dryer’s listing and the manufacturer’s installation instructions.
Look for the exhaust duct size on the data plate.
M1502.4 Transition ducts.
Transition ducts shall not be concealed within construction. Flexible transition ducts used to connect the dryer to the exhaust duct system shall be limited to single lengths not to exceed 8 feet (2438 mm), and shall be listed and labeled in accordance with UL 2158A.In general, an inspector will not know specific manufacturer’s recommendations or local applicable codes and will not be able to confirm the dryer vent's compliance to them, but will be able to point out issues that may need to be corrected.
 
From Dryer Vent Safety - Int'l Association of Certified Home Inspectors (InterNACHI) http://www.nachi.org/dryer-vent-safety.htm#ixzz2jAqjuG2l
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5 Comments

Time for a New Roof

10/9/2013

1 Comment

 
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Ever wonder how far you can let a roof go before replacing it?  
I recently looked at this roof for a buyer, amazingly there were very few leaks in the house.

1 Comment

I love WAZE GPS Social Navigation App

9/30/2013

1 Comment

 
I am loving the WAZE GPS Navigation App on my iPhone.  It gives voice guidance and auto zooms based on your speed.  My favorite feature is the ETA in miles and time, when I put the address in it tells me a ETA, like 5:23pm.  Amazingly it is always right on!  I had one trip that was 85 miles and ended driving through Eugene at 5:30pm, I got home just when it predicted. (I guess traffic is never that bad in Eugene!) It is a social nav app, you can put in information about traffic, road hazards, gas prices, even police on the side of the road. 
My old navigation app was having a lot of issues with it's latest update.  The first photo is of Waze the one I like, the bottom photo is a screenshot from the old app, time for a change!
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1 Comment

Smoke Alarms

5/28/2013

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Smoke Alarms save many lives each year but still over 2,000 people die in fires in their home each year.  Last week my son did some work in his pet snake’s tank in the evening.  The heat lamp which is controlled by a timer was shut off and he set it on a wood shelf.  The next morning we noticed a burning smell that got stronger the closer we were to his room.  The timer had turned the heat lamp on and the lamp was a burning the wood shelf.  My son was sleeping at this time and didn’t notice the smell.  The important part of this story is that there is a two year old ionization type smoke alarm (with a 10 year battery) in his room that did not go off.  We smelled the smoke on a different level of the house, through the closed bedroom door and the newer ionization smoke alarm did not sound. 

There are two main types of smoke alarms, “Ionization” and “Photoelectric”.  Ionization smoke alarms sound quicker in an open “flaming” fire while Photoelectric alarms sound quicker in a “smoldering” fire. 

I saw a local hardware store had a combination Ionization and Photoelectric smoke alarm for $23.  These are sometimes called “smoke and fire” or “dual sensor” alarms.  I bought a Photoelectric alarm for $13 and put it next to the two year old Ionization one.  Thankfully there was no fire at my house and my son and his pets are ok.

Many experts recommend changing smoke alarms every 10 years as the sensors do wear out.  When you push the test button on a smoke alarm and hear a beep, it does not necessary mean the sensor is working, it can just mean the battery has sufficient voltage.

So don’t skimp on smoke alarms!  Replace older ones with dual sensor, “smoke and fire” alarms.  If you have an attached garage or fuel burning appliances be sure to install Carbon Monoxide alarms in or near bedrooms.

I have had the below information in my inspection reports for years and now truly realize that “for the best protection both kinds of smoke alarms are recommend.” 

Smoke alarms are credited with saving many lives over the years. There are two main types of smoke alarms. Photoelectric smoke detectors contain a light source and a light-sensitive electric cell.

Smoke entering the detector deflects light onto the light-sensitive cell, triggering an alarm. Ionizing sensors contain a small amount of americium-241, a radioactive material. It is used to set up a small

electrical current between two metal plates which, when disrupted by smoke entering the chamber, sounds the alarm. In recent years, several national groups have come out with advisories saying that for the best protection, both kinds are recommended.

The National Institute for Standards and Technology tested the two technologies in 2004 and found that ionization smoke detectors sounded in fast, flaming fires an average of 50 seconds earlier than photoelectric detectors. NIST also found that photoelectrics sounded their alarms, on average, 30 minutes earlier than ionization detectors in smoldering fire. Testing by UL last year supported results obtained by the National Institute of Standards and Technology in 2004 that showed ionization detectors sounded sooner in open, flaming fires and that photoelectrics sounded sooner in smoldering fires. Many experts recommend changing smoke alarms every ten years.

The state of Oregon has some of the most comprehensive requirements in the nation regarding smoke alarms in residential properties being sold and in rental properties. Ionization smoke alarms are required to have a "hush" button and a 10 year battery if battery powered.


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    There are always a lot of exciting things happening in homes and new technologies relating to home maintenance.  This is a place to share information about homes.
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